GATE 2026 Environmental Science and Engineering (ES): Syllabus, Eligibility, Books, Exam Dates & PSU Jobs ,Seats in IIT’s, Score,Counselling Process
Preparing for the GATE 2026 Environmental Science and Engineering (ES) exam? You’re in the right place. The GATE (Graduate Aptitude Test in Engineering) is one of the most important national-level entrance exams for students aiming for postgraduate admissions (M.Tech, M.E., Ph.D.) and recruitment in top Public Sector Undertakings (PSUs). Introduced as a dedicated paper in 2021, the Environmental Science and Engineering (ES) paper has become a popular choice among aspirants from diverse academic backgrounds such as Environmental Science, Civil Engineering, Earth Sciences, Chemistry, and Ecology.
In this article, you’ll find complete information about GATE 2026 Environmental Science and Engineering (ES)—including eligibility criteria, exam pattern, detailed syllabus, important dates, and expert preparation tips. Whether you’re a first-time candidate or a repeat aspirant, this guide will help you understand what to expect and how to excel in the GATE ES 2026 exam.
Table of Contents
GATE 2026 Environmental Science Syllabus Section Wise
| Section | Topics |
|---|---|
| 1. Mathematics Foundation | – Linear Algebra: Determinants and matrices, Systems of linear equations, Eigenvalues and eigenvectors. – Calculus: Functions, Limit, Continuity, Differentiability, Local maxima and minima, Taylor series, Tests for convergence, Definite and indefinite integrals, Application of definite integral to obtain area and volume, Partial and total derivatives. – Differential Equations: Linear and non-linear first order ODEs, Higher order linear ODEs with constant coefficients, Cauchy’s and Euler’s equations, Laplace transform and its application in solving linear ODEs. – Probability and Statistics: Descriptive statistics, Central tendency, Dispersion, Skewness and kurtosis, Probability concepts, Conditional probability, Bayes theorem, Risk and reliability, Probability distributions, Correlation, Regression models, Hypothesis testing (t-test, F-test, chi-square test). |
| 2. Environmental Chemistry | – Fundamentals: Covalent and ionic bonding; Chemical equations, concentration and activity; Organic molecule chemistry; Radioactivity; Chemical equilibria; Thermodynamics and kinetics. – Water Chemistry: Water quality parameters; Acid-base equilibria; Buffer solutions; Carbonate system; Solubility of gases; Complexation, precipitation, redox reactions; Inorganic and organic contaminants. – Soil Chemistry: Organic matter, nitrogen, phosphorus, potassium, cation exchange capacity, base saturation, sodium absorption ratio. – Atmospheric Chemistry: Composition of the atmosphere; Reactivity of trace substances; Smog and particulate pollution; Ozone formation; Stratospheric chemistry. |
| 3. Environmental Microbiology | – Microorganisms: Prokaryotic and eukaryotic microbes; Classification; Microbial diversity; Plant-microbe and soil-microbe interactions; Role in wastewater treatment, bioremediation, and biogeochemical cycling. – Cell Biology: Structure of biomolecules (proteins, DNA, RNA, lipids, polysaccharides); Cell structure and function (membrane, wall, organelles). – Metabolism: Anabolism and catabolism; Glycolysis; TCA cycle; Electron transport chain; Fermentation; Enzyme kinetics. – Microbial Growth: Nutrition and growth; Monod’s model; Batch/continuous culture; Environmental effects; Control methods. – Health Aspects: Pathogens; Indicator organisms; Coliform quantification (MPN, membrane filtration). |
| 4. Water Resources & Environmental Hydraulics | Global Water Resources: Structure, properties and distribution of water; Water quality; Threats towater resources; Water conservation. Surface Water Resources: Hydrological cycle and water balance – precipitation, infiltration, evapotranspiration, runoff; Flow hydrographs; Unit hydrographs; Stage-discharge relationship; Reservoir capacity; Reservoir and channel routing; Surface run-off models; Surface water management; Rain water harvesting and storage. Groundwater Resources: Geologic formations as aquifers; Vadose and saturated zones; Confined and unconfined aquifers and their parameters – porosity, permeability, transmissivity and storage coefficient; Darcy’s law and applications; Steady state well hydraulics. Environmental Hydraulics: Concepts of mechanics; Properties of fluids; Pressure measurement; Hydrostatic force on surfaces; Buoyancy and flotation; Laminar and turbulent flow; Flow through pipes; Pipe networks; Boundary layer theory; Forces on immersed bodies; Flow measurement in channels and pipes; Kinematics of flow; Continuity, momentum and energy equations; Channel hydraulics – specific energy, critical flow, hydraulic jump, rapid and gradually varied flow; Design of lined and unlined channels |
| 5. Water & Wastewater Treatment | Water and wastewater quality parameters; Eutrophication and thermal stratification in lakes; River pollution – Oxygen sag curve. Water treatment methods — screening, sedimentation with and without coagulation, filtration, desalination, disinfection; Water distribution and storage Point and non-point sources of wastewater; Population forecasting methods; Design of sewer and storm water sewers; Sewer appurtenances; Preliminary, primary, secondary and tertiary sewage treatment; Sludge generation, processing and disposal methods; Sewage farming. Sources and characteristics of industrial effluents; Concept of Common Effluent Treatment Plants (CETP); Wastewater recycling and zero liquid discharge. Kinetics and reactor design: Mass and energy balance, Order and rate of reactions, Batch reactors, Completely mixed flow reactors, Plug flow reactors. |
| 6. Air & Noise Pollution | Structure of the atmosphere; Natural and anthropogenic sources of pollution; Atmospheric sources, sinks, transport; Indoor air pollution; Effects on health and environment; Air pollution: gases and particulate matter; Air quality standards; Primary and secondary pollutants; Criteria pollutants, ambient and source standards, air quality indices, visibility. Particulate Pollutants: Measurement and control methods; Control of particulate air pollutants using gravitational settling chambers, cyclone separators, wet collectors, fabric filters (Bag-house filter), electrostatic precipitators (ESP). Gaseous Pollutants: Measurement and control methods; Control of gaseous contaminants: absorption, adsorption, condensation and combustion; Control of sulphur oxides, nitrogen oxides, carbon monoxide, and hydrocarbons; Vapour-liquid and vapour-solid equilibria; Diffusion, Fick’s law and interfacial mass transfer. Automotive emission controls, fuel quality, diesel particulate filters, catalytic convertors. Air Quality Management: Point, line and area sources; Inventory; Influence of meteorology – wind rose diagrams, stability, mixing height, topography, dispersion modelling, monitoring. Noise Pollution: Sources; Health effects; Standards; Measurement and control methods. |
| 7. Solid & Hazardous Waste Management | Integrated solid waste management; Waste hierarchy; Rules and regulations for solid waste management in India. Municipal solid waste management: Sources, generation, characteristics, collection and transportation, waste processing and disposal (including reuse options, biological methods, energy recovery processes and landfilling). Hazardous waste management: Characteristics, generation, fate of materials in the environment, treatment and disposal. Soil contamination and leaching of contaminants into groundwater. Management of biomedical waste, plastic waste and E-waste: Sources, generation and characteristics; Waste management practices including storage, collection and transfer |
| 8. Global & Regional Environmental Issues | Global effects of air pollution: Greenhouse gases, global warming, climate change, urban heat islands, acid rain, ozone hole. Ecology and various ecosystems; Biodiversity; Factors influencing increase in population, energy consumption, and environmental degradation. |
| 9. Environmental Management & Sustainable Development | Environmental Management Systems; ISO14000 series; Environmental Auditing: Environmental Impact Assessment; Life cycle assessment; Human health risk assessment. Environmental Law and Policy: Objectives; Polluter pays principle, Precautionary principle; The Water and Air Acts with amendments; The Environment (Protection) Act (EPA) 1986; National Green Tribunal Act, 2010; National Environment Policy; Principles of International Law and International treaties. Energy and Environment: Energy Sources: Overview of resources and reserves; Renewable and non-renewable energy sources; Energy-Environment nexus. Sustainable Development: Definition and concepts of sustainable development; Sustainable development goals; Hurdles to sustainability; Environment and economics. |
| GATE ES Topic Wise Weightage | |
| GATE Environmental Science and Engineering Topics | Weightage |
| General Aptitude | 10 |
| Mathematics Foundation | 10 |
| Environmental Chemistry | 4 |
| Air and Noise Pollution | 6 |
| Water Resources and Environmental Hydraulics | 4 |
| Environmental Microbiology | 5 |
| Solid and Hazardous Waste Management | 9 |
| Environmental Management and Sustainable Development | 6 |
| Water and Wastewater Treatment and Management | 8 |
| Global and Regional Environmental Issues | 3 |
GATE Environmental Science and Engineering (ES) Exam Pattern 2026
| Particulars | Details |
|---|---|
| Exam Mode | Computer-Based Test (CBT) – Online |
| Exam Duration | 3 Hours (180 Minutes) |
| Type of Questions | – Multiple Choice Questions (MCQs) – Multiple Select Questions (MSQs) – Numerical Answer Type (NAT) Questions |
| Number of Sections | 3 Sections: 1. General Aptitude (GA) 2. Engineering Mathematics 3. Environmental Science and Engineering |
| Total Number of Questions | 65 |
| Total Marks | 100 |
| Marks Distribution | – General Aptitude: 15 Marks – Engineering Mathematics: 13 Marks – Environmental Science & Engineering (Core Subject): 72 Marks |
| Marking Scheme | – 1-mark and 2-mark questions – MSQs and NATs have no negative marking – MCQs have negative marking: • 1-mark MCQ: –0.33 • 2-mark MCQ: –0.66 |
| Negative Marking | Applicable only to MCQs |
GATE Environmental Science and Engineering (ES) Eligibility Criteria 2025
To appear for the GATE 2026 Environmental Science and Engineering paper, candidates must meet the following criteria:
🎓 Educational Qualification
| Qualification | Eligible Candidates |
|---|---|
| Bachelor’s Degree | – B.E./B.Tech in Engineering/Technology – B.Sc. (Research)/B.S. from a recognized university |
| Master’s Degree | – M.Sc. in disciplines like Environmental Science, Chemistry, Life Sciences, Earth Science, Ecology, etc. – M.E./M.Tech in Environmental Engineering or related fields |
| Professional Society Examinations | Candidates who have completed sections A or equivalent of professional courses (like AMIE) recognized by UPSC/AICTE/MoE are also eligible. |
| Currently Studying | Final-year or pre-final-year students of qualifying degrees are also eligible. |
📅 Year of Qualification
- Candidates who have completed OR will complete their degree by May/June 2026 are eligible.
🌍 Nationality
| Eligible Nationalities |
|---|
| Indian citizens |
| Foreign nationals from countries like Nepal, Bangladesh, Sri Lanka, Ethiopia, and the UAE can also apply. |
🔁 Number of Attempts
- No limit on the number of attempts for GATE.
GATE Environmental Science and Engineering Section-wise Recommended Books
| Section | Book Title | Author(s) | Publisher | Approx. Price (INR) | Available on Amazon |
|---|---|---|---|---|---|
| 1. Mathematics Foundation | Higher Engineering Mathematics | B.S. Grewal | Khanna Publishers | ₹700 | Yes |
| 2. Environmental Chemistry | Environmental Chemistry | A.K. De | New Age International | ₹500 | Yes |
| 3. Environmental Microbiology | Environmental Microbiology | R.M. Maier, I.L. Pepper, C.P. Gerba | Academic Press | ₹2,800 | Yes |
| 4. Water Resources & Environmental Hydraulics | Hydrology and Water Resources Engineering | K. Subramanya | Tata McGraw Hill | ₹800 | Yes |
| 5. Water & Wastewater Treatment and Management | Wastewater Engineering: Treatment and Reuse | Metcalf & Eddy | McGraw Hill | ₹1,300 | Yes |
| 6. Air and Noise Pollution | Air Pollution Control Engineering | Noel de Nevers | McGraw Hill | ₹1,100 | Yes |
| 7. Solid and Hazardous Waste Management | Integrated Solid Waste Management | George Tchobanoglous | McGraw Hill | ₹2,000 | Yes |
| 8. Global and Regional Environmental Issues | Environmental Studies: From Crisis to Cure | R. Rajagopalan | Oxford University Press | ₹450 | Yes |
| 9. Environmental Management and Sustainable Development | Environmental Management | N.K. Uberoi | Excel Books | ₹500 | Yes |
Recommended Books
-
GATE Environment Science & Engineering [ES] Question Bank 2000+Questions Based on Exam Format MCQ/NAT/Fill the Blank [For 2026]
Original price was: ₹800.00.₹450.00Current price is: ₹450.00. -
GATE Environment Science & Engineering [ES] Sets of 3 Theory Books As Per Updated Syllabus
Original price was: ₹1,800.00.₹1,400.00Current price is: ₹1,400.00.
Jobs Offered for Gate Environmental Science Aspirants, PSU Jobs
✅ Jobs Offered for GATE Environmental Science Aspirants
| Job Type | Organization/PSU | Job Roles | Eligibility Through GATE ES | Remarks |
|---|---|---|---|---|
| Public Sector Undertakings (PSUs) | ONGC (Oil and Natural Gas Corporation) | Environmental Engineer | ✅ GATE ES accepted | Depends on vacancy |
| NTPC (National Thermal Power Corporation) | Environmental Officer/Engineer | ✅ GATE ES accepted | Often requires PG as well | |
| NHPC (National Hydroelectric Power Corp) | Environmental Engineer | ✅ GATE ES accepted | Contractual/permanent | |
| BHEL (Bharat Heavy Electricals Ltd) | Environmental Officer/Consultant | ✅ GATE ES accepted | Rare recruitment | |
| IOCL (Indian Oil Corporation Limited) | Environmental Engineer | ✅ Some posts allow GATE ES | Varies with year | |
| WBPCB (West Bengal Pollution Control Board) | Assistant Environmental Engineer | ✅ GATE ES OR separate exam | State-level recruitment | |
| GSPCB (Goa State Pollution Control Board) | Scientist/Field Officer | ✅ State-based hiring | Competitive |
Public Sector Units (PSUs)
| Organization | Role | GATE ES Accepted? | Typical Salary (CTC) |
|---|---|---|---|
| ONGC, IOCL, HPCL | Environmental Officer / Safety Officer | ⚠️ Few openings, mainly through CE/CH | ₹10–14 LPA |
| BIS (Bureau of Indian Standards) | Scientist ‘B’ | ✅ Yes | ₹9–10 LPA |
| ISRO, DRDO, BARC | Scientist/Engineer SC | ⚠️ No direct ES recruitment; may apply through related streams | ₹8–10 LPA |
| State Pollution Control Boards (SPCBs) | Environmental Engineer/Scientist | ✅ State-level exams | ₹6–9 LPA |
| CPCB | Environmental Officer/Scientist | ✅ Through separate exam or GATE | ₹7–10 LPA |
🎓 IITs Offering M.Tech. in Environmental Science/Engineering
| Institute | Program | Estimated Seats | GATE Paper Accepted | Remarks |
|---|---|---|---|---|
| IIT Bombay | M.Tech. in Environmental Science and Engineering | ~25–30 | ES, CE | Dedicated ES program; accepts GATE ES scores. |
| IIT Delhi | M.Tech. in Environmental Engineering | ~20–25 | CE, ES | Primarily CE; ES acceptance varies by year. |
| IIT Kharagpur | M.Tech. in Environmental Engineering and Management | ~20–25 | CE, ES | Accepts both CE and ES; check annual eligibility criteria. |
| IIT Madras | M.Tech. in Environmental Engineering | ~20 | CE | Currently does not accept GATE ES scores. |
| IIT Kanpur | M.Tech. in Environmental Engineering | ~20 | CE | GATE ES not accepted; CE required. |
| IIT Guwahati | M.Tech. in Environmental Engineering | ~18–20 | CE, ES | Accepts GATE ES scores. |
| IIT Roorkee | M.Tech. in Environmental Management of Rivers and Lakes | ~15–20 | CE, ES | Specialized program; GATE ES accepted. |
| IIT Hyderabad | M.Tech. in Environmental Engineering | ~15–20 | CE | GATE ES acceptance varies; primarily CE. |
| IIT BHU (Varanasi) | M.Tech. in Environmental Engineering | ~15 | CE | GATE ES not accepted; CE required. |
| IIT Dhanbad (ISM) | M.Tech. in Environmental Science and Engineering | ~15–20 | ES, CE | Accepts GATE ES scores. |
| IIT Bhubaneswar | M.Tech. in Environmental Engineering | ~15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Mandi | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Jodhpur | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Gandhinagar | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Ropar | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Patna | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Indore | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Palakkad | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Tirupati | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Bhilai | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Goa | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Jammu | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
| IIT Dharwad | M.Tech. in Environmental Engineering | ~10–15 | CE | GATE ES acceptance varies; primarily CE. |
🎯 GATE ES Score Range for IIT Admissions (General Category)
| IIT | Program | Minimum Score (General) | Remarks |
|---|---|---|---|
| IIT Bombay | M.Tech. Environmental Science & Engineering | 65–72 | Very competitive; high cutoff. |
| IIT Delhi | M.Tech. Environmental Engineering | 60–68 | Varies by specialization; mostly CE-based admission. |
| IIT Kharagpur | Environmental Engineering & Management | 58–65 | Accepts GATE ES and CE. |
| IIT Guwahati | M.Tech. Environmental Engineering | 55–62 | GATE ES accepted. |
| IIT Roorkee | M.Tech. Env. Mgmt. of Rivers & Lakes | 53–60 | Specialized; GATE ES accepted. |
| IIT Dhanbad (ISM) | M.Tech. Environmental Science & Engineering | 50–58 | ES accepted; less competitive than IITB/D. |
Category-Wise Approximate Safe Score (General Trend)
| Category | Safe Score Range (out of 100) |
|---|---|
| General | 55–72 |
| OBC/EWS | 48–65 |
| SC/ST/PwD | 38–50 |
Gate Environmental Science & Engineering Previous Year Question Paper
| Gate Environmental Science PYQ 2022 | Gate Environmental Science PYQ 2024 |
| Gate Environmental Science PYQ 2023 | Gate Environmental Science PYQ 2025 |
Counselling Process
GATE IIT Counselling Process via COAP (2025)
🔹 What is COAP?
- COAP (Common Offer Acceptance Portal) is the platform for M.Tech admissions to IITs.
- It does not conduct admissions but facilitates offer acceptance from different IITs.
- Applicants must apply separately to each IIT and use COAP to accept/reject offers.
🪜 Step-by-Step COAP Counselling Process
| Step | Description |
|---|---|
| 1. Register on COAP | Visit https://coap.iitd.ac.in (or respective year’s portal), register with your GATE Registration number and GATE Score. |
| 2. Apply to individual IITs | Visit each IIT’s M.Tech admissions portal and submit applications separately, mentioning your GATE ES (or CE) score. |
| 3. Participate in COAP Rounds | COAP has multiple rounds (typically 5 main + additional rounds). Participating institutes make admission offers based on your application. |
| 4. Choose Offer Option | In each round, you’ll get options to: <ul><li>Accept & Freeze</li><li>Retain & Wait</li><li>Reject & Wait</li></ul> |
| 5. Final Offer Acceptance | Once you “Accept & Freeze” an offer, visit the respective IIT’s website to complete final admission formalities (document verification, fee payment, etc.). |
🕓 Tentative COAP Timeline (2025)
| Event | Tentative Date |
|---|---|
| COAP Registration Opens | March 2025 |
| Application to IITs | March–April 2025 |
| COAP Round 1 | Mid-May 2025 |
| COAP Round 5 | Mid-June 2025 |
| Additional Rounds | June–July 2025 |
💡 Key Points to Remember
- COAP is mandatory for accepting M.Tech offers from IITs.
- You must apply separately to each IIT (COAP is only for offer coordination).
- You can participate in multiple rounds and upgrade your offer using “Retain & Wait”.
- Offers are made based on GATE score, academic background, and IIT’s selection criteria.
When was GATE ES introduced?
GATE ES was introduced in 2021.
Can non-engineering students appear for GATE ES?
Yes, students with a B.Sc., M.Sc., B.Tech, or BE in relevant disciplines can apply.
Can I appear for GATE ES if I have a background in Civil Engineering?
Yes, Civil Engineering students can appear, but the syllabus differs from GATE CE.
How many questions are asked in GATE ES?
A total of 65 questions.
What types of questions are asked?
MCQs, MSQs, NATs.
Is there negative marking in GATE ES?
Yes, only for MCQs. No negative marking for MSQs and NATs.
What is the qualifying GATE ES cutoff?
Usually ranges between 32–38 marks for General category
How many IITs offer admission through GATE ES?
As of 2024–25, IIT Bombay, IIT Guwahati, IIT KGP, IIT Madras, IIT BHU, and others offer seats.
